When the U2 manager, Paul McGuinness, called the Glastonbury founder, Michael Eavis, last week, he did not have to use many words. "Michael, it is the call you have been waiting for ... " was more than sufficient to let Eavis know that his 26-year quest to get the band to headline the festival was finally over.

Glastonbury organisers confirmed today that U2 will play the Pyramid stage's top spot on Friday 25 June next year. It will be the band's first appearance at Glastonbury, and one of their few on the global festival scene since they hit the pinnacle of their fame.

Eavis had promised something special for Glastonbury's 40th anniversary, and in booking a band who have been rumoured to headline every year since the mid-1980s, he has not disappointed. The ebullient 74-year-old said the news had been a long time coming.

"The 26-year-old rumour has finally come true. At last, the biggest band in the world are going to play the best festival in the world," he said. "Nothing could be better for our 40th anniversary party."

U2 will take a fleeting break from their north American tour to fly over to Somerset, McGuinness said. "The band has always wanted to do Glastonbury one day. This year everyone was in the right mood." Bono sparked a flurry of speculation when he said on BBC radio in February that playing the festival was "something we're working up our whole life to do".

Some expressed doubts that U2 and Glastonbury were a perfect match. Their performance had the potential to be slightly "weird", said Nicola Slade, editor of the music industry newsletter Record of the Day. "They are not going to be able to do their usual U2 spectacular that people have come to expect from them."

The band was accustomed to playing to dedicated fans, not to a more mixed festival crowd, Slade said. "U2 are a divisive band – you either love them or you hate them. I think it will be a difficult audience because it is not their core contingent."

U2's propensity to play large-scale spectacular gigs was one of the reasons they had not yet played the festival, McGuinness said. "I think they have stayed clear of them because they tend to do a big, monster product which doesn't necessarily fit into a festival context."

The band, who will play no other UK gig next year, may opt for a slightly more low-fi affair more in keeping with the Glastonbury vibe and will not bring the 360° tour to Worthy Farm, he said.

Fans of the group can expect a mixture of old and new hits, McGuinness said. The band were excited about playing at such an "English institution", he added. "It's like Wimbledon or the Cup Final."

Tickets for next year's Glastonbury sold out in 24 hours without a sniff of a confirmed headliner. The Guardian is the official media sponsor of the festival.